#include<bits/stdc++.h>
#define ll long long
#define ull unsigned long long
using namespace std;

const int N = 20, INF = 0x3f3f3f3f;

int n, m;
int mp[N][N];
ll f[1 << N][N];
//状态定义： 在st集合中以j为终点的环个数，且默认以编号最小为起点

void solve()
{
    cin >> n >> m;
    for (int i = 1;i <= m;i++) {
        int u, v; cin >> u >> v;
        u--;v--;
        mp[u][v] = mp[v][u] = 1;
    }

    for (int i = 0;i < n;i++) f[1 << i][i] = 1;
    ll ans = 0;
    for (int st = 0;st < (1 << n);st++)
        for (int j = 0;j < n;j++) {
            if (f[st][j] == 0) continue;
            for (int k = 0;k < n;k++) {//枚举出边
                if (mp[j][k] == 0) continue;//不可达，跳出
                if ((1 << k) < (st & -st)) continue;//不可走到比起点更小的位置
                if (st & (1 << k)) {
                    //k到达过，在判断是否构成环
                    if ((1 << k) & (st & -st)) ans += f[st][j];
                } else f[st | (1 << k)][k] += f[st][j];//没有到达过，扩展递推
            }
        }
    cout << (ans - m) / 2;
}

signed main()
{
    //ios::sync_with_stdio(0);
    //cin.tie(0);cout.tie(0);
#define ONLINE_JUDGE
#ifndef ONLINE_JUDGE
    std::istringstream in(R"()");
    std::cin.rdbuf(in.rdbuf());
#endif
    int T = 1;
    //cin>>T;
    for (int i = 1;i <= T;i++) {
        solve();
    }
}